3-5 reps for building strength
6-8 reps for building muscle tissue
10-20 reps for flushing and bulking

Hit a heavy compound for strength, then hit an assistance lift for muscle building, then hit accessory lift with higher reps for flushing and pumping. In other words, don't limit yourself to one rep range, they all have their place.

This is the scheme I used for nearly 20 years. It's the one my mentor taught me and I stuck with it. He taught me: